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Subject: Re: What Was Deep Thought's ICC Rating??

Author: Robert Hyatt

Date: 06:24:56 03/25/03

Go up one level in this thread


On March 25, 2003 at 00:45:03, Uri Blass wrote:

>On March 24, 2003 at 15:04:53, Robert Hyatt wrote:
>
>>On March 24, 2003 at 14:32:19, Uri Blass wrote:
>>
>>>On March 24, 2003 at 13:56:15, Robert Hyatt wrote:
>>>
>>><snipped>
>>>>>>If I had to play Belle today I would _not_ take it lightly.  I'd expect to win,
>>>>>>but I'd know
>>>>>>that Belle was very capable of beating anything in one game.
>>>>>
>>>>>I expect Crafty to win against it even if you use only p90.
>>>
>>>I responded to Belle here and not to deep thought here so your comments are not
>>>relevant.
>>
>>OK.  I overlooked that.
>>
>>Crafty on a P90 is _not_ going to do well against Belle.  Belle searched about
>>170K
>>nodes per second.  Crafty on a P90 is going to be about 1/10th that speed.  I
>>don't think
>>null-move will make up that much ground, since testing with and without
>>null-move in
>>previous years suggested that null-move was worth maybe 50-70 rating points.
>>
>>Crafty on a pentium-pro 200 searches about 64K nodes per second on the bench
>>command, which I just tried to be sure that number was right.
>>
>>That is 2.5X faster than a pentium 133, which is about 1.6X faster than a P90.
>>So the
>>P90 NPS for crafty will bei n the 16K nps range, which is roughly 1/10th the
>>speed of
>>Belle.  Belle's speed is better than three doublings, so crafty is going to have
>>a tough
>>time of it with that machine.
>>
>>Crafty on current hardware would be a totally different animal, but on a P90, it
>>might
>>be ugly.
>>
>>>
>>>I responded only later about Deep thought and
>>>My opinion is that you cannot take lightly Deep Thought but you can expect to
>>>win against it because you are better in tactics(I say it for the hardware of
>>>today and not for p90).
>>
>>I don't think I'm better in tactics than they were/are.  I might have some
>>advantage
>>due to null-move, but then they have singular extensions.  Evaluation is a
>>toss-up as
>>they were not "dumb" by any stretch, since they beat GM players handily.
>
>From the book "how computer play chess" page 192
>
>Table10.1 Correlation between search depth and chess rating.
>
>Depth of search 8  year 1980 program  Belle Rating 2200
>Depth of search 9  year 1986 program Hitech Rating 2400
>Depth of search 10 year 1989 program Deep Thought  2600
>


That's a pretty sensless comparison.  IE would you compare 9 plies from
"the king" to 10 plies from "fritz"?  I wouldn't.  And the comparison is
nonsense.  Hitech was no faster than Belle.  It searched about the same
speed.  Deep Thought was the first (of the three above) that was a quantum
jump in speed.  And with a different search.  Also the years (above) are
wrong.  Belle hit 2200 in 1983.  Ken was given the "life master" certificate
from the USCF at the 1983 WCCC event in New York.  Hitech didn't hit 2400
in 1986 either.  And it was a couple of years before Deep Thought hit 2650+
as well.


>Belle does not seem to be something that beats GM players handily based on this
>data.

No, and neither would crafty on a P90.  Belle beat _several_ GM players at
blitz, which Crafty on a P90 might do also.  But not at 40/2hrs except for
an occasional bit of luck.


>
>There is also a problem to compare results against humans and I prefer to
>compare moves.
>
>I believe that null move is not the only reason for Crafty to be better in
>tactics than
>Belle and there may be other reasons like better order of moves.


Hard to evaluate.  But belle did the capture/passed pawn push extensions, and
it was the first program to try the recapture extension (publicly) and so forth.
It's search was not bad.  It had a full hash table implementation as well,
btw.






>
>Here are some tactical error of Belle from game that it won in 1978 against
>Chess4.7
>
>[D]r2q1rk1/1bp1b1n1/1pn1p2p/p3P1p1/P2p2PP/2PB1N2/1P1BQPN1/R3K2R w KQ - 0 20
>
>bm Qe4

That's the wrong belle.  That machine was searching 5,000 nodes per second,
and was _not_ the belle that played from 1980 on...


>
>Belle blundered by hxg5 but the opponent did not find the right defence.
>
>[D]r2q1rk1/1bp1b1n1/1p2p2p/p3P1P1/Pn1p2P1/2PB1N2/1P1BQPN1/R3K2R w KQ - 0 21
>am gxh6 bm Rxh6
>
>Maybe finding Rxh6 is not easy but avoiding the mistake of Belle(gxh6) is easy
>
>more interesting test position for the programs of today is the following
>position:
>
>[D]r2q1rk1/1bp1b1n1/1pn1p2p/p3P1P1/P2p2P1/2PB1N2/1P1BQPN1/R3K2R b KQ - 0 1
>am Nxb4 bm dxc3
>
>Chess4.7 played Nb4 and in the book it is claimed that it i a good move
>but movei like other programs can fail low on that move after some time and
>prefers dxc3
>



Same thing.  Wrong machine.  the final "belle" was not built until 1980.   The
5K node per second belle came along in 1978.  Prior to that there were other
versions even slower with (for example) just a hardware move generator and
eventually a few other bits and pieces.  But these were nowhere near the the
160-175K nps that 1980 belle hit.



>Uri



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